What change in atomic number occurs when a nucleus emits an alpha particle? a beta particle? a gamma ray?

1. Alpha decay

Alpha particle is a ₂⁴He nucleus. When a parent atom emits an alpha particle, the atomic number reduces by 2 in the formed daughter atom while reducing the mass number by 4. Since atomic number = proton number, due to the decreasing of atomic number, proton number also reduces by 2 in daughter nucleus.

2. Beta emission.

There are two types of beta decay. One is β⁻ and other one is β⁺ emission.

β⁻ emission

β⁻ emission is an emission of an electron by converting a neutron to a proton. Hence, in β⁻ decay, the atomic number increases by 1 and mass number is not changed in the formed daughter nucleus.

β⁺ emission

β⁺ emission is an emission of an positron while converting a neutron to a proton. Hence, in β⁺ decay, the atomic number decreases by 1 and mass number is not changed in the formed daughter nucleus.

3. Gamma decay

In Gamma decay there is no any particle decay from the parent nucleus. Unstable nucleus emits energy photon and becomes as stable by undergoing a gamma decay. Hence, there is no change in atomic number or mass number of the daughter atom.

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.